Mozilla Thunderbird up to 128.6/134.x JavaScript Engine use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.8$5k-$25k0.00

Summaryinfo

A vulnerability labeled as critical has been found in Mozilla Thunderbird up to 128.6/134.x. This affects an unknown part of the component JavaScript Engine. Such manipulation leads to use after free. This vulnerability is documented as CVE-2025-1012. The attack can be executed remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Mozilla Thunderbird up to 128.6/134.x. Affected by this issue is an unknown part of the component JavaScript Engine. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. CVE summarizes:

A race during concurrent delazification could have led to a use-after-free. This vulnerability was fixed in Firefox 135, Firefox ESR 115.20, Firefox ESR 128.7, Thunderbird 128.7, and Thunderbird 135.

The advisory is available at bugzilla.mozilla.org. This vulnerability is handled as CVE-2025-1012 since 02/04/2025. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 10/05/2026).

The vulnerability scanner Nessus provides a plugin with the ID 214959 (Mozilla Firefox ESR < 115.20), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 128.7 or 135 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (214959). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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Vendor

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.9
VulDB Meta Temp Score: 7.8

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

ADP CISA Base Score: 9.8
ADP CISA Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 214959
Nessus Name: Mozilla Firefox ESR < 115.20

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Thunderbird 128.7/135

Timelineinfo

02/04/2025 🔍
02/04/2025 +0 days 🔍
02/04/2025 +0 days 🔍
10/05/2026 +608 days 🔍

Sourcesinfo

Vendor: mozilla.org

Advisory: bugzilla.mozilla.org
Status: Confirmed

CVE: CVE-2025-1012 (🔍)
GCVE (CVE): GCVE-0-2025-1012
GCVE (VulDB): GCVE-100-294626

Entryinfo

Created: 02/04/2025 15:44
Updated: 10/05/2026 18:51
Changes: 02/04/2025 15:44 (23), 02/04/2025 15:47 (33), 02/04/2025 22:11 (2), 02/05/2025 22:17 (3), 04/15/2026 08:30 (22), 09/30/2026 22:43 (3), 10/05/2026 18:51 (1)
Complete: 🔍
Committer: mitr
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Discussion

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